Continuous casting and rolling of metals



July 27, 1965 J. c. BONGIOVANNI CONTINUOUS CASTING AND ROLLING 0F METALSFiled Oct. 28. 1960 10 Sheets-Sheet 1 INVENTOR. JOHN c. BONGIOVANNI BYMJ/ July 27, 1965 J. c. BONGIOVANNI 3,195,516

CONTINUOUS CASTING AND ROLLING OF METALS Filed Oct. 28, 1960 10Sheets-Sheet 2 Fig.1a

July 27, 1965 J. c. BONGIOVANNI 3,196,516

commuous CASTING AND ROLLING OF METALS Filed Oct. 28, 1960 10Sheets-Sheet :5

INVEN TOR. JOHN C. BONGIOVANNI July 27, 1965 J. c. BONGIOVANNICONTINUOUS CASTING AND ROLLING 0F METALS 10 Sheets-Sheet 4 Filed Oct.28, 1960 INVENTOR. JOHN C. BONGIOVANNI /Mw mau w July 27, 1965 J. c.BONGIOVANNI CONTINUOUS CASTING AND ROLLING OF METALS 10 Sheets-Sheet 5Filed Oct. 28. 1960 INVENTOR. JOHN C. BONGIOVANNI July 27, 1965 J. c.BONGIOVANNI 3,

CONTINUOUS CASTING AND ROLLING OF METALS Filed 001;. 28, 1960 10Sheets-Sheet 6 H\ INVENTOR. JOHN c. BONGIOVANN! July 27, 1965 .1. c.BONGIOVANNI CONTINUOUS CASTING AND ROLLING OF METALS Filed Oct. 28. 196010 Sheets-Sheet '7 IN VEN TOR.

JOHN C. BONGIOVANN! BY MM July 27, 1965 J. c. BONGIOVANNI CONTINUOUSCASTING AND ROLLING 0F METALS l0 Sheets-Sheet 8 Filed Oct. 28. 1960INVENTOR. JOHN C. BONGIOVANNI July 27, 1965 J. c. BONGIOVANNI CONTINUOUSCASTING AND ROLLING OF METALS Filed Oct. 28, 1960 10 Sheets-Sheet 9 FIG.IO

FIG. ll

INVENTOR.

JOHN c. BONGIOVANNI BY MM ATTORNEYS July 27, 1965 J. c. BONGIOVANNI3,196,516

CONTINUOUS CASTING AND ROLLING OF METALS Filed Oct. 28. 1960 10Sheets-Sheet 10 FIG. I2 4945- INVENTOR.

JOHN C. BONG IOVANNI 7 ATTORNEYS United States Patent 3,196,516(IONTHNUQUS CASTING AND ROLLING 0F METALS John C. Bongiovanni,University Heights, ()hio (221 Elrntree Road, New Kensington, Pa.) FiledGet. 28, 1960, Ser. No. 65,8l8 '7 lairns. (Cl. 29-33) This is acontinuation-in-part of my application Serial No. 833,538, filed August13, 1959, now Patent No. 3,146,525, issued September 1, 1964.

The present invention is concerned with the direct production of sheetor strip or bar stock from metals in a molten condition. Specificallythe present invention is concerned with method and apparatus whereby amolten metalmay be continuously cast and reduced directly to a sheet orstrip or bar form.

In broad terms, the present invention, insofar as method is concerned,is directed to the formation of a molten body of metal of desiredcomposition, continuously casting the same into an endless slab or ingotform, rectangular or round in cross section, and rolling or reducing thesame while yet in a hot state for example into a continuous strip ofdesired gauge, the strip being then either cut into desired lengths ofsheet or plate, or alternatively coiled and severed at desired coiledlengths. The invention will be discussed in terms of sheet or stripproduction with the metal as cast having a rectangular cross section,but a round section may be used; and also other product sections may beproduced as later described.

With respect to the mill with which the invention is concerned, there isinvolved the combination of a direct casting apparatusof which severaltypes are known to the artfor producing from continuously suppliedmolten metal a vertically descending slab in continuous form ofapproximately the desired final width of the strip or sheet stock; themolten metal being solidified in passing through the mold characteristicof such apparatus and partially cooled by water sprays or jetsimmediately beneath the mold, two sets of pinch rolls spaced below thenozzle serving not only for control of the casting speed for maintenanceof the slab as a moving plug in the casting mold and providing areaction or anchor means for tension to which the slab is subjected inthe heavy reduction; and a vertically reciprocating roller type mill forthe heavy major reduction of the metal.

In the combination a vertically reciprocating pair of rolls on eachdownward stroke engage the slab and are cammed toward each other toproduce a complete reduction of the hot cast slab to desired thickness;While on an upward stroke the rolls, first separated into a non-workingrelation for slab clearance, are returned into working spacing forrte-engagement with the slab at about the top of the stroke. The mainrolling portion of the apparatus-located directly below the casting moldso that the plane or centerline of movement of the metal from the themetal reduction is not absorbed from a power source only during thedownward working stroke, for there is a "ice considerable potentialenergy available for metal reduction in any practical mill at thebeginning of any downward working stroke due to the elevation of themass of the reciprocating rolls and their mounting or carriagestructure; and, therefore, such potential energy is absorbed by or fedinto the reciprocating system also on the nonworking upward stroke ofthe rolls. Hence, the power requirements in the motor or prime mover forthe rolling mill, and also the structural strength needed in elements ofthe power transmission system for the rolls, are lower for example thanin prior horizontal Krause type mills. Also with vertical movement of arollcarriage in contrast with horizontal movement frictional losses inthe moving system can be greatly reduced furthering economy of energyrequirements, and also thereby helping to reduce the structural andpower motor requirements.

The reduction of a continuously cast and endless slab further eliminatesthe waste of prior mills operating horizontally to reduce successivebillets or slabs and resulting in butts or stub ends which cannot gothrough the mill. Also the vertical casting results in bettertemperature control of the metal in solidifying and thereafter inpassing to the reduction region.

A greatly advantageous characteristic of the invention is the fact thatthere is achieved a practically instantaneous reduction, on the order ofas a minimum, in thickness in an effectively hot rolling operationthereby changing the metal structure from an as-cast predominantly largeor average open grain to a uniformly fine grain, with excellenthomogenizing effect, and a consequent great increase in tensilestrengths.

In addition to the above-described features, there are here disclosed aslocated beneath the rolling mill at very economic means for cutting offand handling the finished strip, either in coil form or in fiat sheets.For this purpose there is located immediately beneath the mill apower-operated shearsfor cutting the continuous product strip atappropriate points. Below the shears there are located, as alternativemeans of handling the finished strip, first a coiling apparatus forturning the strip length into say loose coil form; and therebeneath anup-ender device, a tilting sheet receiving and discharging mechanism.From the coiler there is provided a suitable coil ramp or otherconveying means advantageously gravitational, whereby the final coilsare directed to a point of loading or further handling. On the otherhand, where the product is to be in sheet or plate form, the up-ender ortilting receiver accepting each length of material cut from thecontinuous strip in its vertically descending path is thereafter turnedtoward a disposition somewhat beyond horizontal to discharge the severedsheet onto a conveying systemagain advantageously gravitational-forcarrying the same to a final point of loading or other disposition; asfor example to a point where the same are stacked and baled orpalletized.

The general object of the present invention is then the provision of animproved method and apparatus for the production of a continuous metalform from molten metal. Another object is the provision of method andapparatus for direct casting of metal into a continuous ingot andreducing the slab to strip, sheet, plate or bar form. A still furtherobject is the provision of a method and apparatus for achieving a lowcost conversion of merchant metal or molten metal to strip, sheet, plateor bar form,

. mum and alloys thereof, but also ferrousmetals.

particularly non-ferrous metals such as copper and alurni- Other objectandadvantages of the invention will ap- 7 pear from the followingdescription and the drawings wherein: Y a

FIG. 1 and FIG. 1a present in side elevation the rela-,

tions of the principal parts of a plant or mill forfcarrying;

out the method or'process of the present invention; certain parts beingomitted in FIG. 1, and others being represented in generalized oroutline form in FIG. 1a for overall clarity;

FIG. 2 is a somewhat enlarged side viewo'f the principal 1 part of therolling mill proper; FIG. 3 is a front view corresponding to FIG. 2;FIG. 4 is a vertical sectional viewtaken generally as indicated by thelines 44 inFIG. 3"through the reciprocating housing and roll'carriagecontained therein;

FIG. 5 is an irregular transverse sectional view taken;

indicated by the line 55 in 1 FIGS; 3 and 4; i

however, substantially as FIGS. 6 and 7 are front and sideviewsrespectivelyof the roll carriage frame; V I I I FIG. 8 is a fragmentarydetail of aroll camming wedge block; adjustment means; 1

FIG. '9 is'a schematic representation of hydraulic and electric controlcircuitry for the rolling apparatus;

, FIG. 10 is a schematic representation of the positioning in a mill ofthe type described of brushes operating atvarious locations on the slab,pinch rolls, working rolls and product; p

' FIG. 11 is a fragmentary vertical section showing the For handling thestrip-metal produced in the mill M,

there are arranged there-beneath (see FIG. 1a) on a lower floor'a sheardevice S, such as-a Halden type shear, and for manipulation of thesheared product a three roll upcoiler apparatus C into whichthestrip-like product may be directed and there formed into a loosecoil; here again I the apparatus being similar to prior well-knownforms. With the coiling apparatus, for transport or conveyance of afinished coil of desired length away from the mill, 5 there is alsoassociated a conveying device suchas, an inclined guide ramp fordirecting the coils for example to a loading dock. Below the coiler, asan alternately available means of handling the product, there isdisclosed a plate or sheet receiver mechanism or up-ender T, a rollerlined elongated frame which, from a position vertically aligned with thepath of the strip produ'ctto receive the same as it is cut off atappropriate lengths in sheet or plate form by thelshears, is tiltableto, a position slightly beyond horizontal for gravity discharge of thereceived plate to a conveying system carrying the same toa baling areaor loading dock. v 7

' The mill M has a sturdy upright frame comprised of four rigidlyparallel spaced and anchored vertical columns "'10,"such as structuralsteel I'-beams with transverse spacers 10a,'wherein :a heavy integrallycast hollow housing H is guided for vertical reciprocation by four guideroller assemblies 11 at-each corner ofthe housing. A m ill power anddriving system comprises. a' prime mover 12, such as i a three-phasehigh yoltageheavy duty motor; a pair of mounting for a work rollcleaning oscillatory type brush? a FIG. 12 is a further fragmentarysection taken as indi-[- according to the present, invention ispresentedby FIGS.

1, 1a.. Ata top floor of the mill, there is a furnace F- for melting orholding in molten state metal continually poured from the nozzle thereofto be cast through a dielike direct casting mold D into 'a slaborbillet-like continuous. piece B; and immediately below B there aredisposed the I us W, for partially cooling the slab and solidifying thecontrolled continuous water spray jets or cooling apparatfaces of ltheconnecting rod' '19.

reduction gearing units 13,"13 Jon, opposite sides of the mill withinput shafts-coupled by 'a' cross shaft 14, and

(at'the left of FIG. 3) the motor being also connected to the input onone side of, the unit13 by a suitable coupling 15. The output shafts ofthe reduction gearing units Icarry respective suitably counter-balancedfly wheels 17,

each having a crank pin 18 connected through a connecting rod 19 withthe housing H through a wrist pin 20 journalled in bearings inserted inthe housing. Suitable thrust washers are disposed between theinner facesof the wrist pin mounting formations of the housing and the adjacent V aThe roller guide units 11 each'comprise a spacer block or mounting bar21 secured on a respectivecolumn 10 and having rotatably mountedlonadjacent faces series of 'verticallyequispaced rollers 22, 23. Therollers, of one series arestaggered relative to those of the otherseries l and radially project beyond the face of the bar mounting metalwhile yet-in the mold'D. The mold may itself be" water cooled. BelowWare arranged in tandem two pair of pinch rolls, such as a conventionalHorsburg and I ,Scott pinch roll drive, driven at a selected rate'tocontrol 7 the rate of casting or production of'the slab at, D, the

the other;seri es, so that .eachcorner'of the housing is embraced andguided by. rollers 22, 23, bearing on respective vertical finishedareasrunning from top to bottom of the housing. 1 v r .The roll carriageRCis an elongated generally open frame (see FIGS. 6 and ,7) here shownas formed by two pairs'of joined corner angle irons til-l, 4tlr (left"orright pair in FIGSQS and 6) connected by suitable cross struts orbraces, such asfAtla, 41a and 40b,.41b at the'top'and rollsbeing locatedimmediately below and in alignment with D and, W. In general, thefurnace or other means continually pouring metal to the mold producing aslab of desired thickness and Width, the cooling apparatusand the pinchrolls may be similar to those' W611, knownnow' in the art for directCasting processes. Byway of examtoward thebottom respectively, and40,41c and 40d,'41d near the middle of the carriage, the front and backsides 7 between respective members 40-1 and 40-.r being open'and members40ad being set. inwardly therefrom for clear.- ance relative to thehereinafter described camplates 55.

i The carriage also 'is guided and embraced at each corner ple, analuminum slab B may have dimensions'onthei 7 order of 4 by 12 inches inleaving the mold. Where A inch, by 12 inch strip is to be could be castas later noted.

produced, a round billet V reduction ofthe slab thickness. Insofar asthe reduction be said to begener ally similarto that of on finishedareas'by bearing "strip pairs 43 and 44 secured at-corners in thehollowcentral space of the housing, there being also a verticalinward slotateach inside corner of thehousing for accommodation of a corre- Forcontinuous reduction of the slab B to a plate, sheet a spondmg v'emcalcarnage rack may be noted in or strip form, there is further provided onthe next lower floor the reduction or rolling, mill M located verticallybelow the pinch rolls P, the mill M effecting thefmajor FIG. 4, 6 and 8the'ra'cks-32 are carried on the lower end of the cornerangles 40'l;and40-r which extend below the housing H even when the, latter is in itsuppermost position, at which time the carriage RC is in its lowermostposition relative to the housing H, as in FIG. 4.

For'effecting synchronized reciprocation of the roll carriage relativeto thehousing during-reciprocation of the latter on'the millrframe fourrack and pinion mech:

anisms are provided. Each comprises a vertical fixed rack 26 mountedoutboard of a roller support bar 21 and meshed with pinion 27 carried ona transverse shaft within a gearing housing or frame 28, bolted orotherwise secured on a bottom surface of the main casting of the housingH. The pinion 27 is meshed in turn with a gear 29 carried on shaft 30commonly with and rotatable with the pinion 31 meshing with acorresponding carriage rack 32. The pitch diameter of 29 is twice thatof 27 and 31, whereby the movement of the roll carriage is half that ofthe housing H relative to the mill frame.

At opposite sides of the roll carriage RC, in the region between therespective middle vertically paired cross braces 41c, 41c and 40a, 40dthere are formed corresponding parallel transverse slideways 48 forreceiving in each a pair of opposed sliding bearing chock 4%, 49b forthe roll neck bearings. Each chock is of a generally rectangular blockform and has a large central aperture with a sleeve bearing journallingthe roll neck of a corresponding roll R. The bearing checks 4% for oneworking roll, at their upper and lower ends, each have blind bores orholes formed in parallel fashion to receive the ends of verticallyspaced paired single acting hydraulic cylinder units 51, with pistons 52hearing against opposed shoulders on a corresponding one of the facingbearing blocks 45% supporting the other working roll. The cylinder units51 hereinafter called balancing cylinders are constantly pressurized toextend the same in a dash-pot cylinder arrangement, and normally tend tospread the rolls from each other. Accordingly, each chock block 49a isprovided with suitable passageways for hydraulic fluid leading to thebalancing cylinders 51 from flexible hose connections pressured byhydraulic fluid supply system. There is a suitably sized window etweenthe frame members opening into the slideway at each side of the frame,and also in the housing, which are alignable for removal and insertionof the rolls and checks for servicing the assembled mill.

At the front and back sides (top and bottom of FIG. 5) of the verticalcentral opening of the housing H which accommodates the roll carriage,there are like opposed vertically extending channels or recesses whereinare mounted the cam plates 55 by bolts 55b to be vertically fixedrelative to the housing H by thrust plates 550 but shit-table alongbolts 55b toward and away from each other, and each cooperating with arespective one of the rolls R riding thereon. The shape (see FIG. 4) andfunction of the cam plates are hereinafter set forth. The cam plates areurged outwardly by compression springs interposed on each bolt between anut thereon and the housing. Certain control and shifting means for therespective cam plates are also mounted behind the latter in thechannels, including an elongated rather thin wedge plate 56 with itsouter flat face bearing upon a corresponding flat surface 54a of thechannel; and a larger hollow wedge or taper block 58 having sloping face58a complementary to and bearing on the inner sloping face56a of thewedge 56 and an inner fiat face in contact with the fiat outer face ofthe cam plate 55.

It will be noted that the widths of both 56 and 58 are less than thecorresponding dimension of the channel or recess whereby shifting of 56and 58 from one side to the other (i.e., from left to right as viewed inFIG. 5) is permitted. The large taper block 58 has a central recess 58C(see FIG. 8) with parallel vertical walls between which there isreceived a closely fitting nut block 60. A power driven lead oradjusting screw 61 engaged in block 60, journalled at its inner end by asleeve bearing 61a in one wall of the recess 54, extends through and isaxially fixed in a bearinged aperture 61b in the opposite wall byretainers 61C for coupling at 62 to the reversible drive motor andreduction gearing unit 63 bolted to the right side of the housing H.

The taper block 58 is transversely slotted in the region of the screw 61to permit not only axial shifting of the block as it is carried by thenut 50 but also an inward and outward shifting as it is moved along thetaper of the opposed small block 56. The blocks 56 and 58 are alsoslotted transversely at top and bottom for the cam plate bolts 55btherethrough to permit the in-and-out movement of the taper or wedgeblocks.

On the side of the housing H opposite the location of the motor 63 adouble acting hydraulic piston unit 66, as a hydraulic reciprocatingmotor for a corresponding block 56, is mounted for reciprocation indirection transversely of the housing, that is, parallel to thedirection of the lead screw 60 and to the axes of the rolls, and has itspiston coupled to a stud 68 threaded into the broad side of the taperblock.

Considering now the situation of FIG. 5, it is seen that one extremeworking setting, a maximum spacing of the two cam plates from eachother, and hence a maximum spacing of the rolls for any given positionlongitudinally of the cam plates is achieved under the conditions thereappearing with 56 and 58 at the extreme right. However, upon withdrawalto the left of each block 56, as in FIG. 8, the blocks 58 and cam plates55 actually follow so that the rolls immediately separate to clear theslab by action of balancing cylinders 51 upon the roll bearing chocks asin fact is intended to happen at the end of the downward housing orrolling stroke. However, upon simultaneous return of the two plates 56by extending force of the units 66, the cam plates are then urged toreturn to the position of FIG. 5. However, when the power screws drivethe blocks 58 to the left, the opposed tapers of 56 and 58 cause theblocks 58 and hence the cam plates 55 to move inwardly, therebynarrowing the roll spacing. Since the whole structure of the housing H,carriage RC and the other reciprocating components are in generalsymmetrical about the centerplane of the roll carriage, i.e.,centerplane of the continuously cast slab and the product strip, theinward feed or retraction of the blocks 58 should normally be equal; andalso the release and return of the same by operation of cylinders 66should take place simultaneously.

Considering now a typical operation for conversion of aluminum toone-fourth inch plate 12 inches wide, the casting mold or die D of thefurnace would be sized 4 by 12 inches to produce a hot billet ofcorresponding crosssectional dimensions. With the slab entering thepinch rolls at a four inch thickness, and as a typical operatingtemperature at about 850 F., approximately a five percent reduction iseffected at the pinch rolls. Therefore, the slab thickness would be 3.8inches on entering the mill proper. Rolls, each six inches in diameterand sixteen inches long in the roll body, would be typically used in theroll carriage. With a 44 inch stroke of the housing, there is effected acorresponding relative upward movement of twenty-two inches of the rollcarriage relative to the roll housing or a movement of only twenty-twoinches of the carriage downward relative to the mill frame, by virtue ofthe rack and pinion gearing previously described. On the downward orworking stroke of the mill this relative movement of the roll carriagerelative to the housing is in a reverse direction, that is, there is a22 inch vertically upward displacement of the roll carriage relative tothe housing; in other words, on the downward stroke of the housing thistravel being subtracted from the total travel of the housing, thecarriage is carried downward only 22 inches.

In FIG. 4 the relative position of the elements at the extreme upwardposition of the housing is shown in full lines; while the correspondingrelation of the elements at the extreme downward position at the bottomof the stroke is shown in dashed outline for certain elements such asthe rolls and cam plates.

Consider now atypical installation utilizing a 200 horse power motor,rated for 1750 r.p.m. at 440 volts, threephase 60 cycle power with 8foot connecting rods, and a total mass of the reciprocating housing andall elements 7 carried thereby of approximately 10,000 lbs, and 60strokes per'minute forthe working rate. With a four inch thick as-castslab reduced to 3.8 inches infthe I 8- 'Iri the aforedescribedapparatis, the i011 carriage, rolls andhousing, along fwith the auxiliaryequipment carried therebysuch as the hydraulicpistons for the Wedges andpinch rolls feeding at a rate of Vs inch for each working 7 strokecycle, in other Words,.about 1.9 feet per minute at 850 F. and with anelongation factor of 15.2 in the rolling, there isobtainable a deliveryof 5.7 inches "of the inchthick stripor plate per stroke or about 28.5feet per minute or 1710 feet per hour. 'This would then .7

represent a conversion .of about 6480 lbs. per hour of aluminum.

Returning again to FIG. 4, the system is shown just as av downwardstroke. is about to begin. The cylinders 66 are under pressure to drivethe wedges 56 inward and thereby to bring the cam plates to their fixedspacing predetermined by the adjustment of the system. As the housingstarts downwardly, with the carriage lagging, the

cam plates fever-run the descending rolls R, so that sloping camsurfaces in engagement with therolls not only rotate the rolls to causethe adjacent roll surface to move in an upward direction, but also urgethe rolls in wardly. Hence, as the rollfcarriage descends, the'rollsalso the adjusting motors, represent a large moving mass elevatedduringthe upward nonworking stroke, and thereby require a certain'powerinput, not at that. timefused for metal reducing work; The ele'vati on"of this mass'represents an'increase'd potentialenergy of the 'sy'stemwhich reaches its maximum; of. course; at the .top of the upward stroke?Asthe. downward stroke begins, this potential energy then becomesavailable 'as part of the working system expending energy upon themetalbeing worked.

'This' accordingly lessens in some degree the load upon secondly byvirtue of-the fact that the power-demand is are squeezed inwardly,eachfbiting intothe metal and carrying or drawing downward acrest ofmetal on opposite sides of the slab. Over approximately the first halfminimized for the working stroke, a smaller or lighter construction ispossible in many of the working elements of the drive system. 1Furthermore, the very drive motor of the downwardstroke, say 14 inchesofroll descent, Y

the rolls'a're being" brought together. At about one-half of thedownward stroke the rolls have reached the end of the inward cam slopesand there encounter straight parallelcam faces, and accordingly, overnearly the entire remainder of the stroke, the roll spacing is heldconstant at the actual spacing required by the thickness in the finishedproduct. In this latter portion of the stroke,

then, crests of metal advanced'i n the bite are rolled' out into flatsheet form, therolls continuing down even after the sheet has actuallybeen formed in fiat shape for a slight over-rolling portion of thestroke'which may overlap say an inch or so of metal finished on thepreceding V V "ing the otherends to a reservoirreturn line for drivingblocks 56 inwa'rdat one-setting, and reverses the cylinder connectionsto withdraw the blocks-on the' other setting.

stroke, to give a desired'finish' and flatness to the product.

The tandem pinch rolls, conventionally synchronous mo cycle of housingreciprocation. 'matically presented inFIG. 9, includes an electric motorand other 'driveequipment are themselves reduced in size. A generallyconventional. pressurized hydraulic system and components may be used tokeep the balancing cylinders 51 pressurized continuously and to operatethe double acting cylinders 66 tomovej thetaper plates 'or blocks 55 inand out at the stated appropriate points in each full Such a system, vasschedriven pump SOQdeliVeringfluid from: areservoir 81 through anadjustable pressure regulator 82 with relief valve, through flexiblehoses. to the cylinders 51; and also through a" regulator'and reliefvalve 82:: to a two-way tor driven through a very high gear reducti-o'n,restrain the slab to provide tension reactionto, the downwardly appliedforces of the rolls during the downward working stroke, permitting onlythe slab advance corresponding to the established casting rate and feedroll drive is set. V Just before the end of the stroke .is reached, thecylinto which the pinch ders 66 are actuated to retract the same andrelease the cam plates, and also as may be noted from FIG. 4, a veryslight outward taper or cam relief is encountered by. each roll; so thatas t he ,strokeis completed, a slight outward or roll-separatingmovement is permitted under the action of the balancing cylinders. Thus,even before the down sheet portion, so that the normal slab feed isnotimpeded.

ward stroke is quite completed, the rolls'are actually released fromtheir rolling engagement with the finished During the upward or returnstroke, though the housing and cam plates actually will'be overtakingthe carriage rolls'permitting roll clearance ,Wllihlllfi increasingwidth of. the tapered slab end. Just as the carriage is approaching thetop of its stroke, say one inch from the top, control means causes thecylinders 66 again to be' pressurized for extension to drive the wedgeplates 56 inwardly,

thereby again restoring thei cam platesto the original control valve'83, which selectively applies fluid under pressure to the outer endsofthe cylinders 66 while open- 'the moving housing with the pump motorenergized I through flexible electric cables, or alternatively the pumpmay be fixed, independent ofthe housing to which flexible hydrauliclines or hoses are run.

The control valve maybe a solenoidally operated type shifted by solenoid83a fro-m one'sett-ing to the other under the control of single controlswitch 84,;which is tripped or cammed to opposite settings by a set ofspaced lugs 85, 86, the switchjand lug set being on respectiverelatively moving members 'X, Y of which one is fixed, I as the millframe, andthe other i s the reciprocating housing. The'lugs 85, 86 forexample, may be pivoted but spring biased against a stop so that eachmay engage moving in the opposite direction. I On the other hand, the

control valve maybe mechanically 'actuated or tripped to one or theother setting (at the times previously described for ea'chcycle) byencountering vertically spaced dogs'or livery previously stat-ed for'operatiens on aluminum the proper working spacing. The. rolling cycle'then begins again,.in the meanwhile the slab or billet having con-.

to as, as. v a 7 Withthe conditions of billet feed, stroke lengths anddelugs near opposite ends of the housing strokes, similar rollsupporting cam surfaces on a cam plate wouldhave longitudinaldimensions, that is,as projected on a longitudinal'line, a-s follows: asloped surface of about seven and one-half degrees, 13.5 inches ofthelength; a'straight portion of 7.1 inches with 5.7 inches thereofallotted to deliveryf or'rolling out an accumulated biteor crest 1 and1.4'inchesfor over-roll of metal finishedon a previtinuously moved downby of an inch from the posit'ion.

stroke.

ous stroke; and a sharply sloped or release portiornof 1/2inches'ofthe-length' vWithione set of such cam plates as used for firinch thick product obtained in the approximately 16 to 1 reduction froma four inch billet, a product range of 7 to inches is practical from thestated size of billet. However, were it desired to hot roll with agreater reduction say from 4 inches to inch, the billet feed rate wouldpreferably be reduced and the cam slope increased.

With the previously described cam plates and the same feed rates, a 2inch billet thickness would be preferred to produce /s inch productthickness, representing the reduction ratio for which the cams werespecifically designed.

Generally, it may be said that the common metals of ductile character orcapable of normal hot rolling are susceptile to operations as herecontemplated, excepting of course certain special alloys thereof, andthe same cam plates and billet size (therefore direct casting mold) maybe used therewith as for aluminum by varying the rate of billet feed andthe final thickness produced. Of course the temperature of the billet inarriving at the reciprocating rolls is selected according to the hotrolling temperature requirements of the particular metal, e.g. 2000-2200 F. for a 1020 or mild steel; 1800 for copper. Even for thesemetals, where the same reduction ratio of approximately 16 to 1 is usedas first described for aluminum, about the same cam configuration andfeed would be used, the specific energy requirements merely demandingvaried power.

The temperature of the metal actually being cast into the mold will, aswell known to the art, depend upon the specific metal composition andmold environment; for example with various aluminum alloys requiringtemperatures over a range easily as broad as 12001500 F.

In a schematic fashion, FIG. 10 shows disposed on opposite sides of thepath of billet travel a pair of rotationally driven Wire brushes 11%disposed below the location of the cooling water spray system and abovethe pinch rolls P, for the purpose of cleaning the slab of any scale orother adherent debris; two pairs of rotary cleaning brushes 11)]. forthe pinch rolls P each contacting a respective roll substantiallydiametrically opposite the point of roll contact with the slab; twopairs of slabcleaning rotary brushes 162 and 193 respectively below thepinch roll and below the range of movement of the working roll carriage.As various type mounting and drives for these rotary bristle brushes areknown to the art they are no further described here.

More importantly, for cleaning the working rolls and preventing the samefrom going out of correct effective shape by accumulation of scale orthe like, these rolls are each provided with a bristle brushlongitudinally oscillated parallel to the roll axis. More usually thebristle brushes operating on the slab are wire bristle brushes, whilethose for cleaning the various rolls are comprised of natural organic orsynthetic plastic bristles for protection of roll finish, though attimes metal brushes may be used.

One suitable form of mounting for the oscillating brushes 164 within theroll carriage is shown in the fragmentary views of FIGS. 11 and 12 ofone brush mounting. The elongated brush 1114 is secured in a pair ofspaced clamps 105 each having its base slidably mounted on a respectivepin 1% secured on a slide block 1117. The slide blocks 167 (see FIG. 12)are mounted below, and for oscillation parallel to, the correspondingroll by vertically spaced parallel rods 108 and 169 having endsrespectively fixed in and slidably supported at opposite sides of theroll carriage frame; the blocks being slidable on fixed rod 1% andsecured in fixed parallel spaced relation on slidable rod 1&9.

To oscillate the blocks 187 and hence the brush 104, depending inclinedcams 111, 112 are secured to the vertically reciprocating housing H insuch position as to be contacted by respective opposite rounded ends ofthe rod 161?, so that as the roll carriage itself reciprocatesvertically in the housing, the rod 109 is carnmed endwise 1% in oppositedirection on up and downwardly carriage movement by the correspondinglyformed surfaces of the cam plates.

The brush clamps 1% are slidably mounted on the respective parallel pins1% so that they may follow the rolls in and out relative to the slab tomaintain cleaning contact therewith; and accordingly means must beprovided to move each brush along with its roll, while permitting thebrush itself to oscillate endwise. One means for this purpose (see FIG.12) is the use at the end of each brush of a short channel shaped brushguide 114 secured to the outer end of the adjacent bearing chock as at4% and disposed in the general orientation of clamp to embrace thecorresponding brush end in slidable relation.

In place of the use of a mold with a rectangular opening, a mold may beused having a circular discharge opening for casting a round billet.This may be desirable in some instances from cost considerationsinasmuch as round molds for direct casting are more readily available asstandard items, and also from an operational viewpoint. Where four inchstrip, for example, i the desired product, a four inch diameter roundbillet would be cast.

Other product forms that may be produced by the method and apparatus ofthis invention are shown by way of example in FIGS. 13a where 130, 13Gdesignates the cross section of a pair of square rods which are rolledin continuous length; in 13b, where 131, 131 designate the crosssections of a pair of round rods or bars which may be rolled incontinuous lengths; and in PEG. 130, where 132 designates the crosssection of a bar form in effect comprised of two opposed outwardlydivergent roughly wedge shaped or triangular portions 132L, 132R mergedor joined at their apical regions, providing a continuously rolledstock, which may be vertically longitudinally slit at the centralnarrowed region to provide two wedge shaped bars suitable for use, forexample, in production of commutator segments.

The roll form must of course be changed from the cylindrical form usedin production of plate or strip stock to a contoured roll form of suchshape that when the opposed working rolls are at their position ofclosest approach to each other in the working stroke, the intersectionsof the proximate surfaces of the two rolls with a plane through the rollaxes defines or is substantially identical with the shape of theopposite sides of the desired product. Thus in FIG. 13a the rolls havecooperating opposed circumferential grooves 135 of right angle crosssection; while in FIG. 1312 the grooves 136 have a semicircular crosssection. For the product indicated by 130, the rolls will have the formshown in FIG. 14 where, beginning at a region spaced inward from eachend, a roll tapers or diverges outwardly toward the middle of the roll.

Furthermore with change in the roll form it may be necessary toaccommodate the transverse shape of the cam plates to the shape of therolls, as indicated also in FIG. 14 where the cam plates 55 have ashallow recess 140, triangular in cross section extending longitudinallyto the inclined and straight portions of a cam throughout its length, toaccommodate the circumferential central bulge produced on the roll bythe outwardly tapering port-ions 137, 137, while the opposite sidemarginal portions of the cam plate face 141, 141 may retain the sameflat form disclosed for the cam plates where flat stock is being rolled,to support the cylindrical end portions of the roll face. The recess 148may be of such shape that it merely provides clearance with respect tothe roll bulge or it may actually support the central part of the roll,as may be required by working stresses produced under particularoperating conditions. Where the roll form is varied from a cylindricalshape merely by circumferential grooves and the remaining portions ofthe interrupted cylindrical surface provide adequate bearing surface,the straight and inclined portions of the cam working face may betransversely flat, as would beithecase said pinch roll means.

in FIGS.- l3a or 13b. a It will be noted that the form of the productbar of for the roll 'forms used FIG. 13c (seealso FIG. 14) is such thatthe loads imposed 1 upon the rolls are balanced along the rollaXis,since the product form is symmetrical about a vertical longitudinal 1central plane;.and for a like purpose of balancing stressfor loadsinFIGS. 'l3a'and 13b the rolls are grooved to pro duce two squareelements or two round elements from the continuously cast billet or bar,which in'all threeof the- 'FlGURES lsa, b and c is round in crosssection as indi V cated by the dashed circle 145 in ea'ch case.

I claim: a i a j 1. A mill for the continuous conversion .ofmetal into arolled form from molten metal comprising: a direct casting mold forproducing a moving straight hot billet from molten metal, billet coolingmeans located adjacent saidmold for maintaining the metal in solidbillet form as it leaves the mold, constant speed power-driven tandempinch roll means engaging said billet on the side of 'said cooling meansremote from the mold to control the rate of delivery of said billet fromthe mold, vertically reciprocating cooperating paired roll means adaptedto engage there-between successive increments of the billet length and ito move toward each other to a predetermined spacing during a firstportion of each working stroke away from the mold andthereafter to bemaintained at said spacing for substantially the remainder of thestroke,'and means to separate said rolls during the return stroke to aspacing exceeding the thickness of the billet as delivered from 2; Amill for the continuous conversion of metal'into a rolled form 'frommolten metal comprising: a direct casting mold for producing aver'tically descending hot billet from molten metal, billet cooling:means located adjacently below said mold'for maintaining the metal insolid of each pair respectively engaging the back-oi a cam plate and aninner wall of the housing, means for shifting a first of said blocks ina vertical plane to a selected position to predetermine a workingspacing for the rolls, and means for quickly'retracting and advancingthe second Wedge block from and into wedging engagement relative to thefir st, as the' housing approaches the bottom of a downward stroke andthe top of an upward return stroke respectively; said cam plates havinglike roll camming iaces in-clu-ding'respective slopedi-lower surfacesmutually upw-ardlyconvergent and respective substantially vertical- V'ly straight mutually parallel upper surfaces. 7

6. A'mill for thecontinuou's conversion of metal into a rolled form frommolten'meta-l comprising; means for producing a verticallydescending'hot billet directly from molten metal,constant speed tandempinch roll means engaging said billet below the first said meansto'determine'a delivery rate of said billet, a rigid frameand a housingmounted and guided thereon for vertical reciprocatiommeans forreciprocating'the housing,;a roll carriage vertically. guided in saidhousing with said billet extending therethrough, vertical racks on theframe and carriage and gear means meshing with said racks for re-'ciprocating the: carriage in lagging rela-tion to the housing, a pairof horizontally spaced horizontalrolls mount- 6d insaidoarriage onopposite sides of the billet path for movement toward anda-way from thebillet, a pair of vertically extended cam plates for backing'upthe'respechot. billet form as it leaves the mold, constant speed tandempinch roll means-engaging "said billet below said cooling means tocontrol therate ofzdescent of said billet from the mold, verticallyreciprocating cooperating paired roll means adapted toengagetherebetween successive-in:

V crements of thebillet length and to move toward each other to apredetermined spacing during a first portion of each workingdownwardgstroke and thereafter to be malntained at said spacing forsubstantially the remainder of the stroke, and means to separate saidrolls during the return stroke to a spacing exceeding the thickness ofth mine a delivery rate of said billet, a'rigid frame and a housingmounted and guided there-on for vertical reciprocation, means forreciprocating the housing, a roll car riage vertically guided in saidhousing with'said billet extending therethr-ough, vertical rack-son theframe and of metal into tive rolls,' said plates vertically fixed insaid housing and shiftably mounted for varying horizontal spacingbetween the rolls, 'means biasing the rolls away from each other againstcam surfaces on the respective cam plates, and

respective means supported between each said cam plate and'the housing.for adjusting. the working spacing and releasing the rolls; the lastsaidmeans including a pair of cooperating wedge blocks having facesincontact with each other, saidblocks of each pair respectively engagingthe back of a cam plate and an innerwall of the housing, meansforshifting a first of s-aid'blocks in a vertical plane to a selectedposition to predetermine a Working spacing for the rolls, and means forquickly retracting and advancing the second wedge block in a verticalplane from and into wcdging engagementrelative to the first, as thehousing approaches the bottom of a downward stroke and the top of. anupward return stroke respeci tively; said camgplates having like rollcamming faces ineluding respective sloped lower surfaces mutuallyupwardly convergent and respective substantially vertically aIstraigh-tmutually parallel upper surfaces.

, V ,50 4. A mill as described in claim 3, including means for 7. A mill'for the continuous conversion of metal into 7 a rolled formfrom'mo'lten metal comprising: means for producing a verticallydescending billet directly from molten met-aL constantspeed tandem pinchroll means I engaging said billet below the first said means todeterruins a feed rate of said billetpa rigid frame and a housmg mountedand. guided thereon forve'rtical reciprocatron below the pinch rollmeans, power driven means for reciprocatingthe housing, a roll carriagesupported and guided in said housing for vertical reciprocation along astud billet extend ng therethrough, cooperating means on the frame andcarriage for reciprocating thecarriage in carriage and gear meansmeshing with said racks for re ciprocating the carriage in laggingrelation to thehousmg, I

a pair of horizontally spaced horizontal rolls'mounted'in said carriageon opposite sides of the billet path for movement toward and away fromthe billet,,a pair of V611,

tically extended cam plates fo'rbacking' up the respective rolls, said:plates vertically fixed in said housing and hor'i zon-tally shiftablymounted for'varying horizontal spacing between said rolls, andrespective mean-ssupportedL between each said cam plate and the housingfor adjusting the working spacing and releasing the rolls; the last a 7said means including a pair of wedge blockshavingcom plime ntalfilysloped cooperating contact-faces, said blocks lagging relation to thehousing, a pair of horizontally Spaced horizontal rolls horizontallyshiftably mounted in but vertically fixed relative to said carriage onopposite sides of thebillet path for movement toward and away from thebillet, .a pair of variably spaceable. vertically extended. roll'backing cam plates mounted in said housing, and means supported in thehousing and acting on the cam plates for establishing a d-ownwar-dstroke Work- 'ing spacing of. the plates and for releasing the platesand thereby'the' r-ollsqas theihousing approachesthe top of anupwardreturn stroke and the bottom of a downward working strokerespectively; said cam plates having like roll camrning faces includingrespectively sloped lower surfaces mutually upwardly convergent torespective sub- 13 14 stant-ially vertically straight mutually papallelupper 2,791,8 12 5/57 Dangelzer 225 7.2 surfaces. 2,827,944 3/58 Grossu29- 3313 References Cited by the Examiner 2,854,732 10/ 5 8 Hessenberg29528 UNITED STATES PATENTS 2, 07,151 10/ 59 Peterson 29-33- 13 9,47112/ 52 Field 2 5 FOREIGN PATENTS Norton France- 406345 7/ 89 Norton2933-3 519 979 4/40 Great Britain 441,374 1 1/9O Norton 2 9--33.3705,721 7/02 Trotz 2933.3 I i t 2,139,215, 12/38 Waggon 29 528 10 RCHARD H. EANB Prlmary r- 2 739 323 4 5.7 Ackemnan t 22 57 2 WHITMORE A.WILTZ, HYLAND BIZOT, Examiners.

7. A MILL FOR THE CONTINUOUS CONVERSION OF METAL INTO A ROLLED FORM FROMMOLTEN METAL COMPRISING: MEANS FOR PRODUCING A VERTICALLY DESCENDINGBILLET DIRECTLY FROM MOLTEN METAL, CONSTANT SPEED TANDEM PINCH ROLLMEANS ENGAGING SAID BILLET BELOW THE FIRST SAID MEANS TO DETERMINE AFEED RATE OF SAID BILLET, A RIGID FRAME AND A HOUSING MOUNTED AND GUIDEDTHEREON FOR VERTICAL RECIPROCATION BELOW THE PINCH ROLL MEANS, POWERDRIVEN MEANS FOR RECIPROCATING THE HOUSING, A ROLL CARRIAGE SUPPORTEDAND GUIDED IN SAID HOUSING FOR VERTICAL RECIPROCATION ALONG A SAIDBILLET EXTENDING THERETHROUGH, A COOPERATING MEANS ON THE FRAME ANDCARRIAGE FOR RECIPROCATING THE CARRIAGE IN LAGGING RELATION TO THEHOUSING, A PAIR OF HORIZONTALLY SPACED HORIZONTAL ROLLS HORIZONTALLYSHIFTABLY MOUNTED IN BUT VERTICALLY FIXED RELATIVE TO SAID CARRIAGE ONOPPOSITE SIDES OF THE BILLET PATH FOR MOVEMENT TOWARD AND AWAY FROM THEBILLET, A PAIR OF VARIABLY SPACEABLE VERTICALLY EXTENDED ROLL BACKINGCAM PLATES MOUNTED IN SAID HOUSING, AND MEANS SUPPORTED IN THE HOUSINGAND ACTING ON THE CAM PLATES FOR ESTABLISHING A DOWNWARD STROKE WORKINGSPACING OF THE PLATES ADN FOR RELEASING THE PLATES AND THEREBY THE ROLLSAS THE HOUSING APPROACHES THE TOP OF AN UPWARD RETURN STROKE AND THEBOTTOM OF A DOWNWARD WORKING STROKE RESPECTIVELY; SAID CAM PLATES HAVINGLIKE ROLL CAMMING FACES INCLUDING RESPECTIVELY SLOPED LOWER SURFACESMUTUALLY UPWARDLY CONVERGENT TO RESPECTIVE SUBSTANTIALLY VERTICALLYSTRAIGHT MUTUALLY PARALLEL UPPER SURFACES.